If you can use tin snips to cut the tube away it will be easier. But you have to make a cut through the edge of the locknut and into the area where the tube is. Then since the face of the locknut will prevent it from being split continuing the cut across the face of the locknut over to the center opening will give enough latitude that when you drive a screwdriver into the slot you made, (parallel to the valve body so you do not damage it), the nut should separate a little bit. That little bit will be enough to relieve the pressure and allow you to unscrew it.: hj you keep on saving my bacon, and I appreciate it. I'm having a hard time picturing the cut you talk about, though. Can you guide me through it? Can you describe it another way?: